In this study, one of the mean-field theories in nematics, the Maier-Saupe
theory (MST), is generalized within Tsallis thermostatistics (TT). The vari
ation of the order parameter versus temperature has been investigated and c
ompared with experimental data for p-azoxyanisole (PAA). So far, we believe
that this is the first attempt at the application of TT in liquid crystals
. It is well known that MST fails to explain the experimental data for some
of the nematics, one of which is PAA. However, generalized MST is able to
account for the experimental data for a long range of temperatures. Also, i
n this study, the effect of nonextensivity is shown for various values of t
he entropic index. (C) 2001 Elsevier Science B.V. All rights reserved.